C / C++ / MFC

1. Fire up a browser and visit www.google.com.
   
   
2. In the search box, type "multidimensional arrays". (Omit the quotes.)
   
   
3. You'll see a page of links. Click on the second link (www.eskimo.com/~scs/cclass/notes/sx4ba.html).
   
   
4. Read the page content.

Todd Smith

#include "memory.h"
#include "new.h"
//
void main()
{
	int x = 4, y = 7, z = 9; // 3D array
	int i, j, k;
//
	// Allocate memory
	int nSize = x * y * z * sizeof(int);
	int* p = (int*)::operator new(x * y * z * sizeof(int));
	int* q = p; // Used while creating the array
	::memset(p, 0, nSize); // Initialize all array data to zero
//
	// Create the array
	int*** a = new int**[x];
	for (i = 0; i < x; i++)
	{
		a[i] = new int*[y];
		for (j = 0; j < y; j++)
		{
			a[i][j] = new (q) int[z];
			q += z;
		}
	}
//
	// Set values to all values in the array
	for (i = 0; i < x; i++)
	{
		for (j = 0; j < y; j++)
		{
			for (k = 0; k < z; k++)
			{
				a[i][j][k] = i + (j * x) + (k * x * y);
			}
		}
	}	
//
	// Deallocate the array -  NB! No destruction
	for (i = 0; i < x; i++)
	{
		delete[] a[i];
	}
	delete[] a;	
	::operator delete(p);
}

<br />
class Cell {<br />
.. whatever each cell stores<br />
  };<br />
class Row {<br />
..<br />
..<br />
..<br />
Cell &operator[](const int idx);<br />
<br />
}<br />
<br />
class Matrix {<br />
 ..<br />
..<br />
<br />
 Row &operator[](const int idx);<br />
<br />
};<br />
<br />

<br />
Matrix mat(...);<br />
Cell v1,v2;<br />
mat[row][column] = v1;<br />
<br />
v2 = mat[row][col];<br />
<br />